JP4460568B2 - Receiver, transceiver, and control method - Google Patents

Description

  The present invention relates to a receiver, a transceiver, and a control method for transmitting information in contact with a communication medium such as a conductor floating from a human body or a ground.

  Due to the miniaturization and high performance of portable terminals, wearable computers that can be worn on the human body have been attracting attention. Conventionally, as information communication between such wearable computers, an electric field communication transceiver is connected to and attached to a computer, and an electric field induced by the electric field communication transceiver is transmitted through a human body that is an electric field transmission medium. There has been proposed a method for transmitting and receiving.

  FIG. 10 shows a conventional electric field communication system. The transmitter 221 of the mobile device 220 connected to the mobile terminal 224 modulates and outputs information (data) to be transmitted output from a small computer (not shown) with a carrier wave having a predetermined frequency f by the modulation / output unit 222. The output data is transmitted to the stationary apparatus 210 using the human body 200 as an electric field transmission medium. In the stationary apparatus 210, data from the human body 200 that is in contact with the reception electrode 214 is received by the reception unit 213 inside the receiver 212. The received data is output from the receiver 212 to the computer 211.

The transmitter 221 is away from the ground, and a stray capacitance C _g 227 is generated between the circuit ground 225 and the ground. In addition, stray capacitance C _b 226 is generated between the human body 200 and the ground. In the conventional technique, the reactance unit 223 is inserted between the transmission circuit (modulation / output unit 222) and the transmission / reception electrode 228, and the human body 200 is caused by the stray capacitance (stray capacitance _Cg 227, stray capacitance _Cb 226) and the resonance phenomenon. The applied voltage signal is increased to realize electric field communication (see, for example, Patent Documents 1 and 2).
JP 2004-153708 A (Patent No. 375099) United States Patent Application Publication, Pub, No .: US2004 / 009226A1 Pub, Date: May 13. 2004 (Patent No ,: US 7069062 Pub, Date: Jun. 27. 2006)

  However, in the conventional technology, in a communication system in which an electric signal is induced in a human body as an electric field transmission medium and communication is performed by detecting the electric signal, the electric signal is significantly attenuated. Therefore, it is necessary to increase a transmitter output. Yes The power consumption of the transmitter was large.

  Further, since an electric field transmission medium such as a human body is not electrically shielded, there is a possibility that electromagnetic waves are radiated around it.

  In addition, a configuration using a transmitter that modulates the impedance between the human body and the ground and a receiver that detects this modulation is known, but the input impedance of the receiver used is in contact with the human body or in the surrounding environment. If it changes significantly, there is a possibility that the component to be detected changes and cannot be demodulated normally.

  In view of the above problems, the object of the present invention is to reduce the power consumption of the transmitter or transceiver during transmission and the electromagnetic waves radiated to the surroundings, and correct the change in the input impedance of the receiver or the detected component due to the change in the external environment. It is possible to enable stable communication in a wider application range.

  To achieve the above object, the present invention according to claim 1 is a receiver for communicating between communication devices in contact with or close to a communication medium, and receiving means for receiving the communication; A variable input reactance connected in parallel with the receiving means for changing the reactance value of the receiving means and improving the receiving sensitivity of the receiving means.

  According to a second aspect of the present invention, in the first aspect, the variable input reactance is controlled by changing a reactance value by a control signal output from the receiving unit.

Further, the invention according to claim 3, Oite to claim 2, wherein the control signal corrects the change in the impedance value of each of the contact or proximity with the communication medium with the communication device.

  Moreover, this invention of Claim 4 is provided with the receiver in any one of Claims 1-3, It is a transceiver characterized by the above-mentioned.

  According to a fifth aspect of the present invention, in the control method of a receiver for performing communication between communication devices that are in contact with or close to a communication medium, a step of receiving the communication by a reception unit; and the reception unit Changing a reactance value of the reactance value in the variable input reactances connected in parallel to improve the receiving sensitivity of the receiving means.

  According to a sixth aspect of the present invention, in a receiver for performing communication between communication devices in contact with or close to a communication medium, an electrode for detecting an impedance between the communication medium and a ground, A detection signal source for generating and outputting a detection signal used to detect impedance between the communication medium and the ground, an amplification / filter unit for amplifying the detection signal and performing filtering, and the communication medium and the ground An impedance detection demodulation / control unit for correcting a signal component of information to be received restored based on an impedance between grounds, and an input reactance variable by an input reactance control signal output from the impedance detection demodulation / control unit A variable input reactance unit.

  Further, the present invention according to claim 7 is the mixer according to claim 6, wherein the impedance detection demodulation / control unit mixes a signal from the electrode and a reference signal of the signal source for detection, and the mixer A control / determination unit for demodulating a signal based on information to be received from the output of the output and outputting the input reactance control signal.

According to an eighth aspect of the present invention, in the seventh aspect , the impedance detection demodulation / control unit controls the variable input reactance unit by the input reactance control signal and corrects a signal component to be detected. An adjustment signal for performing is output to the detection signal source and the mixer.

  According to a ninth aspect of the present invention, in a receiver for performing communication between communication devices in contact with or close to a communication medium, an impedance between the communication medium and a ground is detected and applied to the communication medium. An electrode for receiving a signal electric field based on the received information to be received, a detection signal source for generating and outputting a detection signal used for detecting an impedance between the communication medium and the ground, and the detection signal A preamplifier for amplifying a signal electric field based on the information to be received applied to the receiving electrode, and a resonance state should be detected based on an impedance between the communication medium and the ground to receive the signal. Outputs data output start signal for starting demodulation and output of signal based on information, and impedance detection demodulation and control for correcting detected signal component A first filter unit for passing only a signal based on the information to be received, a second filter unit for allowing only the detection signal to pass, and when the data output start signal is input Demodulator for demodulating and outputting a signal based on the information to be received, and functioning when detecting a resonance state of a transmitter transmitting the signal based on the information to be received, A variable input reactance unit for changing a reactance value by an input reactance control signal output from the control unit, and in response to the data output start signal, the electrode and the input reactance unit are connected to each other in the reception state, A connecting portion for connecting the electrode and the variable input reactance portion to each other during the detection;

  According to a tenth aspect of the present invention, there is provided a transceiver for performing transmission and reception between communication devices that are in contact with or close to a communication medium. In the transceiver, the impedance between the communication medium and the ground is detected. An electrode for receiving a signal electric field based on information to be received applied to the communication medium and applying a signal electric field based on information to be transmitted in the transmission to the communication medium; and between the communication medium and the ground Impedance modulation for performing the transmission by modulating the reactance value of a variable reactance unit connected to the electrode and capable of varying its own reactance value so as to make the impedance of the impedance based on the information to be transmitted Generates and outputs a detection signal used to detect impedance between the transmitter and the communication medium and the ground. A signal source for detection, an amplification / filter unit for amplifying and filtering the detection signal, and a signal component of information to be received restored based on an impedance between the communication medium and the ground An impedance detection demodulation / control unit for performing, a variable input reactance unit for varying an input reactance value by an input reactance control signal output from the impedance detection demodulation / control unit, and the electrode and the impedance modulation in the transmission A transmission / reception switching unit configured to connect a transmission unit and connect the electrode and the variable input reactance unit in the reception.

  Further, in the present invention described in claim 11, the impedance detection demodulation / control unit according to claim 10, wherein the impedance detection demodulation / control unit mixes a signal from the electrode and a reference signal of the signal source for detection, and the mixer A control / determination unit for demodulating a signal based on information to be received from the output of the output and outputting the input reactance control signal.

Further, the invention according to claim 12, in claim 1 1, wherein the impedance detection demodulation and control unit performs control of the variable input reactance section by the input reactance control signal, the signal component to be detected An adjustment signal for correction is output to the detection signal source and the mixer.

  According to a thirteenth aspect of the present invention, there is provided a transceiver for performing transmission and reception between communication devices that are in contact with or close to a communication medium. In the transceiver, the impedance between the communication medium and the ground is detected. An electrode for receiving a signal electric field based on information to be received applied to the communication medium and applying a signal electric field based on information to be transmitted in the transmission to the communication medium; and between the communication medium and the ground Based on a detection signal source for generating and outputting a detection signal used to detect the impedance of the signal, an amplification / filter unit for amplifying and filtering the detection signal, and an impedance between the communication medium and the ground An impedance detection demodulation / control unit for correcting the signal component of the information to be received restored by The reactance value is changed based on the reactance control signal from the impedance detection demodulation / control unit, and the impedance between the communication medium and the ground is changed to the impedance value based on the information to be transmitted in the transmission. A variable reactance unit for changing a reactance value, a data / modulated signal conversion unit for outputting a control signal for making an impedance value according to the information to be transmitted in the transmission to the variable reactance unit, and A transmission / reception switching unit for connecting the electrode and the signal source for detection in reception and disconnecting the connection in transmission.

  According to a fourteenth aspect of the present invention, in any one of the tenth to thirteenth aspects, the impedance detection demodulation / control unit adjusts a reactance value of the variable reactance unit in the transmission to adjust a circuit ground and a ground ground. A reactance adjustment function unit is provided to resonate with the stray capacitance between them.

  The present invention according to claim 15 is the circuit ground and communication medium according to any one of claims 10 to 13, wherein the impedance detection demodulation / control unit adjusts a reactance value of the variable reactance unit in the transmission. And a reactance adjustment function unit for resonating with the stray capacitance between the ground and the ground.

  According to a sixteenth aspect of the present invention, in the method for controlling a receiver for performing communication between communication devices that are in contact with or close to a communication medium, the step of detecting an impedance between the communication medium and the ground at an electrode Generating and outputting a detection signal used for detection of impedance between the communication medium and the ground in the detection signal source, amplifying and filtering the detection signal in an amplification / filter unit, and impedance detection A step of correcting a signal component of information to be received restored based on an impedance between the communication medium and the ground in the demodulation / control unit; and an input reactance output from the impedance detection demodulation / control unit in the variable input reactance unit Variable input reactance by control signal It has a step that, a.

  According to a seventeenth aspect of the present invention, there is provided a receiver control method for performing communication between communication devices in contact with or close to a communication medium, wherein an impedance between the communication medium and the ground is detected at an electrode. Receiving a signal electric field based on information to be received applied to the communication medium; generating and outputting a detection signal used for detecting an impedance between the communication medium and the ground ground in a detection signal source; Amplifying a signal electric field based on the detection signal and the information to be received applied to the receiving electrode in a preamplifier, and based on an impedance between the communication medium and the ground in an impedance detection demodulator / controller Data output for detecting a resonance state and starting demodulation and output of a signal based on the information to be received A step of outputting a start signal and correcting a signal component to be detected; a step of passing only a signal based on the information to be received in a first filter unit; and a step of passing only the detection signal in a second filter unit A step of demodulating a signal based on the information to be received when the data output start signal is input in the demodulator, and a signal based on the information to be received in the variable input reactance unit And a function of changing a reactance value by an input reactance control signal output from the impedance detection demodulation / control unit, and a connection unit according to the data output start signal. In the reception state, the electrode and the input reactance unit are connected to each other, and the detection time is And a step of connecting the said electrode variable input reactance section together.

  According to another aspect of the present invention, there is provided a transceiver control method for performing transmission and reception between communication devices that are in contact with or close to a communication medium. Detecting a signal impedance and receiving a signal electric field based on information to be received applied to the communication medium, applying a signal electric field based on information to be transmitted in the transmission to the communication medium, and an impedance modulation transmitter In order to set the impedance between the communication medium and the ground to an impedance value based on the information to be transmitted, the reactance value of a variable reactance unit connected to the electrode and capable of changing its reactance value is modulated. Performing the transmission and between the communication medium and the ground in the signal source for detection. A step of generating and outputting a detection signal used for impedance detection, a step of amplifying the detection signal in an amplification / filter unit and filtering, and an impedance detection demodulating / control unit for detecting an impedance between the communication medium and the ground A step of correcting a signal component of information to be received restored based on the step, a step of varying an input reactance value by an input reactance control signal output from the impedance detection demodulation / control unit in a variable input reactance unit, and a transmission / reception switching unit And connecting the electrode and the impedance modulation transmitter in the transmission, and connecting the electrode and the variable input reactance unit in the reception.

  According to a nineteenth aspect of the present invention, there is provided a transceiver control method for performing transmission and reception between communication devices that are in contact with or close to a communication medium. Detecting a signal electric field based on information to be received applied to the communication medium, applying a signal electric field based on information to be transmitted in the transmission to the communication medium, and a detection signal source Generating and outputting a detection signal used for detecting an impedance between the communication medium and the ground, and amplifying and filtering the detection signal in an amplification / filter unit, and an impedance detection demodulation / control unit in the step Information to be received restored based on the impedance between the communication medium and the ground. And a variable reactance unit that changes a reactance value of the variable reactance unit based on a reactance control signal from the impedance detection demodulation / control unit in the reception, and between the communication medium and the ground in the transmission. A step of changing the reactance value so that the impedance is an impedance value based on the information to be transmitted, and a control signal for setting the impedance value according to the information to be transmitted in the transmission in the data / modulation signal converter Are output to the variable reactance unit, and the transmission / reception switching unit connects the electrode and the detection signal source in the reception, and disconnects the connection in the transmission.

  According to the present invention, power consumption of a transmitter or transceiver during transmission and electromagnetic waves radiated to the surroundings can be reduced, and a change in input impedance of a receiver or a detected component due to a change in an external environment can be corrected. Stable communication can be achieved within the applicable range.

<First Embodiment>
FIG. 1 shows a configuration diagram for explaining the first embodiment.

  FIG. 1 shows a receiver 1, a computer 2 integrally connected to the receiver 1, an electrode 10 formed by combining an insulator 11 and a receiving electrode 12, an amplification / filter unit 3, A detection signal source 4, a detection signal source output impedance 5, an impedance detection demodulation / control unit 6, a receiver control / data determination unit 7, and a mixer 8 are shown.

  In the configuration of FIG. 1, a variable input reactance unit 9 is connected to an electrode 10 that is an external input to the receiver 1, and good communication is performed with a transmitter (not shown) by adjusting this. In this adjustment, an input reactance control signal is generated by the receiver control / data determination unit 7 in order to correct the component detected by the impedance detection demodulation / control unit 6, and this input reactance control signal is sent to the variable input reactance unit 9. The input is variably corrected.

  Next, FIG. 2 shows a configuration diagram of the entire communication system according to the first embodiment, and the operation of the communication system will be described.

If the communication medium 15 such as a human body carrying the impedance modulation transmitter 20 which modulates the impedance is in contact with the electrode 10, the admittance Y ₁ between the electrodes 10 and the earth ground is expressed by the following equation.

In Equation (1), X _v and R _rct are a reactance component and a resistance component of the variable reactance unit 23 in the impedance modulation transmitter 20, respectively. 1 / _Brcv is the reactance of the variable input reactance unit 9 of the impedance detection receiver 1. C _b 17 , C _g 18 are stray capacitances between the communication medium 15 and the ground, and between the circuit ground 27 and the ground, respectively. Further, ω is each frequency of the detection signal output from the detection signal source 4, and j represents (−1) ^1/2 .

X _v of the variable reactance section 23 of the impedance modulation transmitter 20 is changed by the modulation signal. When the data on the impedance modulation transmitter 20 is modulated input signal based on the data are input to the variable reactance section 23, the admittance Y ₁ between the electrodes 10 and the earth ground varies with the data. The data is transmitted from the impedance modulation transmitter 20 to the impedance detection receiver 1 by restoring the data based on the change of Y ₁ detected by the impedance detection receiver 1.

The admittance in the case where the communication medium 15 is not in contact is Y ₁ = jB _rcv , and Y is different from the fluctuation due to the change in the variable reactance unit 23 of the impedance modulation transmitter 20 before and after the communication medium 15 contacts the electrode 10. ₁ fluctuates. At this time, since the intensity and phase of the signal applied to the electrode 10 from the detection signal source output impedance 5 changes, in order to detect the change in admittance (or impedance) with high accuracy, the signal when the communication medium 15 contacts is detected. It is necessary to correct the intensity and phase.

FIG. 3 shows the change of admittance | Y ₁ | and the signal of each part when correction is not performed. In FIG. 3A, | Y ₁ | changes during a period when the human body as the communication medium 15 is approaching the electrode 10. In FIG. 3A, only the size is shown, but the phase also changes.

  When the impedance detection sensitivity is designed to be high with the expectation of detecting a change in impedance due to data with high sensitivity, the output range of the mixer 8 is limited as shown in FIG. The range becomes narrow, the output of the mixer 8 is saturated, and data cannot be restored.

  Further, when the impedance detection range is wide (sensitivity is low) as shown in FIG. 3B in order to cope with the change when touched, it is difficult to detect the change in impedance due to data.

  Therefore, in the first embodiment, the variable input reactance unit 9 is corrected to correct a change in a signal applied to the electrode 10 (a signal input to the amplification / filter unit 3) due to contact with the communication medium 15. . The output of the mixer 8 in the impedance detection demodulation / control unit 6 changes before and after the contact with the communication medium 15, and output from the receiver control / data determination unit 7 in the impedance detection demodulation / control unit 6 in order to cancel this change. The reactance of the variable input reactance unit 9 is adjusted by the input reactance control signal.

Next, FIG. 4 shows | Y ₁ | and signals of the respective parts when corrected.

First, when | Y ₁ −B _rct | changes as shown in FIG. 4 (1), the change is canceled as shown in FIG. 4 (2) (the output of the mixer 8 is changed as shown in FIG. 4 (4)). Therefore, the reactance control signal changes B _rct to make | Y ₁ | constant as shown in FIG. For this reason, even if the sensitivity of impedance detection is increased, data can be restored without saturating the output of the mixer 8 when the communication medium 15 touches the electrode 10. In this configuration, even if the stray capacitance _Cb or the like changes due to a change in the electrical environment around the communication medium 15 or the transmitter / receiver while the communication medium 15 is in contact with the electrode 10, the change can be corrected. is there.

  In the conventional electric field communication, since the electric signal is significantly attenuated, it is necessary to increase the output of the transmitter, the power consumption of the transmitter is large, and the communication medium 15 such as a human body is not electrically shielded. There is a possibility of radiation, and countermeasures have been an issue. Therefore, by providing the configuration of the present embodiment, such a problem can be solved, and when the change in the input impedance of the receiver due to contact with the communication medium 15 is large, or around the communication medium 15 and the transmitter / receiver Even when changes in the electrical environment cannot be ignored, a highly sensitive receiver with a wide impedance detection range, that is, a receiver capable of stable communication can be provided.

  Even in the case of detecting the resistance component, it is difficult to detect only the resistance component accurately in practice, so the configuration of the present embodiment is effective.

  The following two types of data demodulation are possible. When the data transmission speed is low, the admittance modulation by the data to be detected is also corrected, so that the data can be demodulated from the input reactance control signal. On the other hand, when the data transmission rate is high, the change in the input reactance control signal cannot follow the admittance modulation by the data to be detected, so that the data can be demodulated from the output of the mixer 8 (FIGS. 4 (5) and 4 (6)). Describe the case).

The frequency of the detection signal is assumed to be about 10 kHz (kilohertz) to 100 MHz (megahertz), but is preferably about 5 MHz to 10 MHz. Here, 1 kHz = 10 ³ Hz and 1 MHz = 10 ⁶ Hz. In addition, the literature "" Personal Area Networks. Near-field intrabody communication ", TGZimmerman. IBM SYSTEMS JOURNAL VOL 35 (1996), pp.609-617 " is C _b According to 100pF, C _g is on the order of 10fF ~1pF is there. The influence of C _b 17 is large before and after the contact with the communication medium 15, and the variable range of B _rcv is designed to include the change in admittance due to C _b 17 at the frequency of the detection signal. Further, B _rcv includes the stray capacitance between the electrode 10 and the ground, and the susceptance of the wiring or cable connecting the electrode 10. JB _rcv + j ωC _b can be large changes in Y ₁ due to the modulation of the reactance component X _v of the variable input reactance section 9 of better impedance modulation transmitter 20 to reduce the impedance detection demodulation and control including this and C _b 17 Data can be restored even if the sensitivity of the unit 6 is low.

<Second Embodiment>
FIG. 5 shows a block diagram of the second embodiment.

  In the present embodiment, the detection signal source 4 and the mixer 8 are also provided with a mechanism for performing correction using the parameter adjustment signal 30 in order to provide a margin for correction of the signal intensity and phase when the communication medium 15 comes into contact. Yes. By adjusting the phase of the reference signal output from the detection signal source 4 by the parameter adjustment signal 30 and the amplitude of the detection signal output to the variable input reactance unit 9 and adjusting the conversion gain of the mixer 8, the variable input It is possible to cope with larger fluctuations in impedance than when only the reactance unit 9 corrects.

  Although the case where the ground of the circuit of the impedance detection receiver 1 is connected to the ground is described, the impedance can be corrected even when the ground of the circuit of the impedance detection receiver 1 is floating from the ground. . In this case, fluctuations in impedance between the ground of the circuit of the impedance detection receiver 1 and the ground are corrected. When the variable reactance unit 23 is modulated on the impedance modulation transmitter 20 side, the impedance between the communication medium 15 such as a human body and the ground ground changes, and the ground of the circuit of the impedance detection receiver 1 floats from the ground ground. Communication is possible even when

<Third Embodiment>
FIG. 6 shows a third embodiment.

  In the present embodiment, the impedance detection receiver 100 includes a transmission / reception switching unit 31, and an impedance modulation transmission unit 32 that transmits data by modulating the impedance between a communication medium such as a human body and the ground is added to form a transceiver. is doing.

  When receiving, the a2 and c2 of the transmission / reception switching unit 31 are connected by the transmission / reception switching signal 35, and the electrode 10 and the variable input reactance unit 9 are connected. At the time of transmission, a2 and b2 of the transmission / reception switching unit 31 are connected, and the electrode 10 and the impedance modulation transmission unit 32 are connected. Data output from the computer 2 at the time of transmission is converted into a modulation signal by the data / modulation signal conversion unit 33 and input to the variable reactance unit 34 to change the reactance of the variable reactance unit 34.

  This change is detected by another receiver (not shown) that is in contact with another part of the human body, which is a communication medium, or a receiver of a transceiver, and data is restored. Even in this configuration, communication is possible even if the circuit ground is floated from the ground.

  In addition, in order to adjust the reactance value of the variable input reactance unit 9 to a value that causes resonance with the stray capacitance of the circuit ground or the stray capacitance of the communication medium in contact with the electrode 10, the reactance adjustment is performed in the impedance modulation transmission unit 32. May be added.

  Further, FIG. 7 shows a modification of the third embodiment.

  In this modification, the variable reactance unit 38 serves as the variable input reactance 9 shown in FIG. 6 and the variable reactance 34 for modulation during transmission at the time of reception. At the time of reception, the reactance of the variable reactance unit 38 is adjusted by the reactance control signal so that the change of the output of the mixer 8 in the impedance detection demodulation / control unit 6 before and after contact with the communication medium is made constant with the modulation signal kept constant. . The data is restored by the impedance detection demodulation / control unit 6 and output to the computer 2.

  At the time of transmission, the connection of the transmission / reception adjustment switching unit 39 is disconnected by the transmission / reception switching signal 35, and the reactance value of the variable reactance unit 38 is a value that causes resonance with the floating capacitance of the circuit ground or the floating capacitance of the communication medium in contact with the electrode. It adjusts by reactance control signal. Thereafter, the transmission data output from the computer 2 is converted into a modulation signal by the data / modulation signal conversion unit 33 and input to the variable reactance unit 38, and the reactance value of the variable reactance unit 38 is changed.

  With the above operation, the impedance detection demodulation / control unit 6 performs receiver control and data determination so as to cancel the output change at the time of reception, and at the time of transmission, the reactance value of the variable reactance unit 38 is a value that causes resonance. A receiver control / data determination / reactance adjustment unit 37 that performs reactance adjustment. The reactance value of the variable reactance unit 38 is adjusted to a value that resonates with the stray capacitance between the circuit ground and the ground ground or the stray capacitance between the circuit ground and the communication medium and the ground ground.

<Fourth embodiment>
8 and 9 are configuration diagrams of the fourth embodiment.

In this embodiment, the transmitter is combined with the receiver of the electric field communication transceiver, and the transmitter mounted on the communication medium such as the human body 50 in contact with the electrode 10 resonates with the surrounding stray capacitances C _b 17 and C _g 18. Data is output from the electric field communication demodulator 41 only when

  FIG. 9 shows a configuration diagram of a communication system according to a fourth embodiment to which the configuration of FIG. 8 is applied.

The modulation / output unit 122 of the electric field communication transmitter 120 modulates a signal having a predetermined frequency with data input from the terminal and outputs the modulated signal to the variable reactance unit 121. The variable reactance unit 121 has a reactance value that resonates with the stray capacitances C _b 17 and C _g 18 only when a signal is output, and efficiently applies the signal to a communication medium such as the human body 50. The receiver 110 monitors the resonance state of the electric field communication transmitter 120 with the impedance detection / control unit 6, and outputs a data output start signal to the electric field communication demodulation unit 41 when the electric field communication transmitter 120 enters the resonance state. And start demodulating data.

  When the resonance state of the electric field communication transmitter 120 is not detected on the receiver 110 side, a1 and c1 of the switch 45 are connected, and the electrode 10 and the variable input reactance unit 9 are connected. The detection signal input to the variable input reactance unit 9 is detected by the mixer 8 of the impedance detection / control unit 6 through the preamplifier unit 40 and the second filter unit 43, and the impedance between the receiving electrode and the ground is measured. Monitoring changes. At this time, the receiver control / determination unit 7 corrects the intensity and phase of the signal when the communication medium comes into contact.

  When the resonance state is detected, a1 and b1 of the switch 45 are connected by a data output start signal, and the electrode 10 and the input reactance unit 44 are connected. The signal from the electric field communication transmitter 120 transmitted to the electrode 10 passes through the preamplifier 40 and the first filter unit 42, and then is demodulated by the electric field communication demodulator 41 to restore the data.

  With this configuration, stable communication is possible even when the change in the input impedance of the receiver 110 due to contact with the communication medium is large, or when the change in the electrical environment around the communication medium and the transmitter / receiver cannot be ignored. It is possible to provide a highly independent receiver that can block data from a parasitic communication path.

  According to the embodiments described above, it is possible to reduce the power consumption of the transmitter or transceiver during transmission and the electromagnetic waves radiated to the surroundings, and to correct the change in the input impedance of the receiver or the detected component due to the change in the external environment Thus, stable communication can be achieved in a wider application range.

The block diagram for demonstrating 1st Embodiment is shown. 1 shows a configuration diagram of an entire communication system according to a first embodiment. FIG. | Y ₁ | and the signal waveform of each part when not corrected are shown. | Y ₁ | and the signal waveform of each part when corrected are shown. The block diagram of 2nd Embodiment is shown. The block diagram of 3rd Embodiment is shown. The modification of 3rd Embodiment is shown. The block diagram of 4th Embodiment is shown. The block diagram of the communication system of 4th Embodiment is shown. An explanatory view for explaining a conventional electric field communication system is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Impedance detection receiver 2 ... Computer 3 ... Amplification / filter part 4 ... Detection signal source 5 ... Detection signal source output impedance 6 ... Impedance detection demodulation / control part 7 ... Receiver control / data determination part 8 ... Mixer 9 ... Variable input reactance unit 10 ... electrode 15 ... communication medium 20 ... impedance modulation transmitter

Claims (19)

In a receiver for communicating between communication devices in contact with or close to a communication medium,
Receiving means for receiving the communication;
A variable input reactance connected in parallel with the receiving means to change its reactance value and improve the receiving sensitivity of the receiving means;
A receiver comprising: The variable input reactance is:
The receiver according to claim 1, wherein the change of the reactance value is controlled by a control signal output from the receiving unit. The control signal is
The receiver according to claim 2, wherein a change in impedance value in each of contact or proximity between the communication medium and the communication device is corrected.   A transceiver comprising the receiver according to claim 1. In a control method of a receiver for performing communication between communication devices in contact with or close to a communication medium,
Receiving the communication at a receiving means;
Changing the reactance value of the variable input reactance connected in parallel with the receiving means to improve the receiving sensitivity of the receiving means;
A method for controlling a receiver. In a receiver for communicating between communication devices in contact with or close to a communication medium,
An electrode for detecting an impedance between the communication medium and the ground,
A detection signal source for generating and outputting a detection signal used for detecting an impedance between the communication medium and the ground, and
An amplification / filter unit for amplifying and filtering the detection signal;
An impedance detection demodulation / control unit for correcting a signal component of information to be received restored based on an impedance between the communication medium and the ground;
A variable input reactance unit for varying an input reactance by an input reactance control signal output from the impedance detection demodulation / control unit;
A receiver comprising: The impedance detection demodulation / control unit is
A mixer for mixing a signal from the electrode and a reference signal of the detection signal source;
A control / determination unit for demodulating a signal based on information to be received from the output of the mixer and outputting the input reactance control signal;
The receiver according to claim 6, comprising: The impedance detection demodulation / control unit is
It performs control of the variable input reactance section by the input reactance control signal, claim and outputs an adjustment signal for correcting the signal component to be detected in the mixer and the detection signal source 7 Receiver as described in. In a receiver for communicating between communication devices in contact with or close to a communication medium,
An electrode for detecting a signal electric field based on information to be received applied to the communication medium by detecting an impedance between the communication medium and the ground; and
A detection signal source for generating and outputting a detection signal used for detecting an impedance between the communication medium and the ground, and
A preamplifier for amplifying a signal electric field based on the detection signal and the information to be received applied to the receiving electrode;
A resonance state is detected based on the impedance between the communication medium and the ground, and a data output start signal for starting demodulation and output of a signal based on the information to be received is output, and a signal component to be detected is corrected. Impedance detection demodulation and control unit for performing,
A first filter unit for passing only a signal based on the information to be received;
A second filter unit for passing only the detection signal;
A demodulator for demodulating and outputting a signal based on the information to be received when the data output start signal is input;
Variable input for changing the reactance value by the input reactance control signal output from the impedance detection demodulation / control unit, which functions when detecting the resonance state of the transmitter that is transmitting the signal based on the information to be received A reactance section;
In response to the data output start signal, the electrode and the input reactance unit are connected to each other in the reception state, and a connection unit for connecting the electrode and the variable input reactance unit to each other at the time of detection,
A receiver comprising: In a transceiver for transmitting and receiving each other between communication devices in contact with or close to a communication medium,
In the reception, an impedance between the communication medium and the ground is detected, a signal electric field based on information to be received applied to the communication medium is received, and a signal electric field based on the information to be transmitted in the transmission is received in the communication medium. An electrode for application to,
In order to set the impedance between the communication medium and the ground to an impedance value based on the information to be transmitted, the reactance value of a variable reactance unit connected to the electrode and capable of varying its reactance value is modulated to An impedance modulation transmitter for transmitting;
A detection signal source for generating and outputting a detection signal used for detecting an impedance between the communication medium and the ground, and
An amplification / filter unit for amplifying and filtering the detection signal;
An impedance detection demodulation / control unit for correcting a signal component of information to be received restored based on an impedance between the communication medium and the ground;
A variable input reactance unit for varying an input reactance value by an input reactance control signal output from the impedance detection demodulation / control unit;
A transmission / reception switching unit for connecting the electrode and the impedance modulation transmission unit in the transmission, and connecting the electrode and the variable input reactance unit in the reception;
A transceiver comprising: The impedance detection demodulation / control unit is
A mixer for mixing a signal from the electrode and a reference signal of the detection signal source;
A control / determination unit for demodulating a signal based on information to be received from the output of the mixer and outputting the input reactance control signal;
The transceiver of claim 10. The impedance detection demodulation / control unit is
It performs control of the variable input reactance section by the input reactance control signal, claim and outputs an adjustment signal for correcting the signal component to be detected in the mixer and the detection signal source 1 1. The transceiver according to 1. In a transceiver for transmitting and receiving each other between communication devices in contact with or close to a communication medium,
In the reception, an impedance between the communication medium and the ground is detected, a signal electric field based on information to be received applied to the communication medium is received, and a signal electric field based on the information to be transmitted in the transmission is received in the communication medium. An electrode for application to,
A detection signal source for generating and outputting a detection signal used for detecting an impedance between the communication medium and the ground, and
An amplification / filter unit for amplifying and filtering the detection signal;
An impedance detection demodulation / control unit for correcting a signal component of information to be received restored based on an impedance between the communication medium and the ground;
In the reception, the self reactance value is changed based on a reactance control signal from the impedance detection demodulation / control unit, and in the transmission, the impedance between the communication medium and the ground is based on the information to be transmitted; A variable reactance unit for changing the reactance value as much as possible;
A data / modulated signal converter for outputting a control signal for making an impedance value corresponding to the information to be transmitted in the transmission to the variable reactance unit;
A transmission / reception switching unit for connecting the electrode and the detection signal source in the reception and disconnecting the connection in the transmission;
A transceiver comprising: The impedance detection demodulation / control unit is
The reactance adjustment function part for adjusting the reactance value of the said variable reactance part in the said transmission, and making it resonate with the stray capacitance between a circuit ground and earth grounds is provided. Transceiver. The impedance detection demodulation / control unit is
The reactance adjustment function part for adjusting the reactance value of the said variable reactance part in the said transmission, and making it resonate with the floating capacitance between a circuit ground and a communication medium, and a ground ground is provided. Transceiver according to In a control method of a receiver for performing communication between communication devices in contact with or close to a communication medium,
Detecting an impedance between the communication medium and a ground at an electrode;
Generating and outputting a detection signal used for detection of impedance between the communication medium and the ground in the detection signal source;
Amplifying and filtering the detection signal in an amplification / filter unit; and
Correcting the signal component of the information to be received restored based on the impedance between the communication medium and the ground in the impedance detection demodulation / control unit;
Varying the input reactance by an input reactance control signal output from the impedance detection demodulation / control section in the variable input reactance section;
A method for controlling a receiver. In a control method of a receiver for performing communication between communication devices in contact with or close to a communication medium,
Detecting an impedance between the communication medium and ground at an electrode and receiving a signal electric field based on information to be received applied to the communication medium;
Generating and outputting a detection signal used for detection of impedance between the communication medium and the ground in the detection signal source;
Amplifying a signal electric field based on the information to be received applied to the detection signal and the reception electrode in a preamplifier;
In the impedance detection demodulation / control unit, a resonance state is detected based on the impedance between the communication medium and the ground, and a data output start signal for starting demodulation and output of the signal based on the information to be received is output. Correcting signal components to be detected;
Passing only a signal based on the information to be received in the first filter unit;
Passing only the detection signal in a second filter unit;
Demodulating and outputting a signal based on the information to be received when the data output start signal is input in a demodulator;
The variable input reactance unit functions when detecting the resonance state of the transmitter that is transmitting the signal based on the information to be received, and the reactance value is changed by the input reactance control signal output from the impedance detection demodulation / control unit. Step to
In response to the data output start signal in the connection unit, the electrode and the input reactance unit are connected to each other in the reception state, and the electrode and the variable input reactance unit are connected to each other at the time of detection,
A method for controlling a receiver. In a transceiver control method for transmitting and receiving data to and from each other between communication devices in contact with or close to a communication medium,
An electrode detects the impedance between the communication medium and the ground ground in the reception, receives a signal electric field based on information to be received applied to the communication medium, and receives a signal electric field based on information to be transmitted in the transmission Applying to the communication medium;
The reactance value of the variable reactance unit connected to the electrode and capable of varying its reactance value so that the impedance between the communication medium and the ground ground is an impedance value based on the information to be transmitted in the impedance modulation transmission unit. And performing the transmission,
Generating and outputting a detection signal used for detection of impedance between the communication medium and the ground in the detection signal source;
Amplifying and filtering the detection signal in an amplification / filter unit; and
Correcting the signal component of the information to be received restored based on the impedance between the communication medium and the ground in the impedance detection demodulation / control unit;
Varying an input reactance value by an input reactance control signal output from the impedance detection demodulation / control unit in a variable input reactance unit;
Connecting the electrode and the impedance modulation transmitter in the transmission in a transmission / reception switching unit, and connecting the electrode and the variable input reactance unit in the reception;
A method for controlling a transceiver, comprising: In a transceiver control method for transmitting and receiving data to and from each other between communication devices in contact with or close to a communication medium,
An electrode detects the impedance between the communication medium and the ground ground in the reception, receives a signal electric field based on information to be received applied to the communication medium, and receives a signal electric field based on information to be transmitted in the transmission Applying to the communication medium;
Generating and outputting a detection signal used for detection of impedance between the communication medium and the ground in the detection signal source;
Amplifying and filtering the detection signal in an amplification / filter unit; and
Correcting the signal component of the information to be received restored based on the impedance between the communication medium and the ground in the impedance detection demodulation / control unit;
The variable reactance unit changes its reactance value on the basis of the reactance control signal from the impedance detection demodulation / control unit in the reception, and the impedance between the communication medium and the ground in the transmission is based on the information to be transmitted. Changing the reactance value to obtain an impedance value;
Outputting to the variable reactance unit a control signal for making an impedance value corresponding to the information to be transmitted in the transmission in the data / modulated signal conversion unit;
Connecting the electrode and the signal source for detection in the reception in the transmission / reception switching unit, and disconnecting the connection in the transmission;
A method for controlling a transceiver, comprising:

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